[docs] quotas apply to image-volume-cache owner

Add a note that even though there are configuration options
governing the number and total GB consumed by volumes in the
image-volume-cache, the internal tenant configured as the
cache owner is nonetheless subject to quotas, which can affect
the actual amount of stuff cached.

Change-Id: Ice12d2f7401fa481bb410c7518bfc436d90bb86a
Closes-bug: #2045984
This commit is contained in:
Brian Rosmaita 2023-12-08 09:16:23 -05:00
parent e9f9415789
commit 5b59d85dc0

View File

@ -18,6 +18,8 @@ instead of downloading the image contents and copying data to the volume.
The cache itself is configurable per back end and will contain the most The cache itself is configurable per back end and will contain the most
recently used images. recently used images.
.. _internal-tenant:
Configure the Internal Tenant Configure the Internal Tenant
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@ -89,6 +91,20 @@ cache entries will be configured as:
image_volume_cache_max_size_gb = 200 image_volume_cache_max_size_gb = 200
image_volume_cache_max_count = 50 image_volume_cache_max_count = 50
.. note::
As mentioned above, the :ref:`internal tenant<internal-tenant>` configured
as the cache owner does not require any special permissions and is subject
to quotas like any other user. Hence, it is possible that the quotas for
the internal tenant may need to be adjusted to allow the internal tenant
to hold at least ``image_volume_cache_max_count`` volumes not exceeding
``image_volume_cache_max_size_gb`` total size. Thus, although the default
value for these image volume cache settings is ``0`` (unlimited), in
practice, these will be limited by the quotas that apply to the internal
tenant.
See :doc:`../cli/cli-cinder-quotas` for more information.
Notifications Notifications
~~~~~~~~~~~~~ ~~~~~~~~~~~~~